Rodents, which account for over 40% of mammalian species and occupy diverse terrestrial ecosystems, are major reservoirs for zoonotic viruses, including Coronaviridae, Hantaviridae, and Arenaviridae. However, the rodent species acting as central hubs for viral diversity and transmission remain poorly defined. To address this, we conducted systematic sampling across 18 counties and cities on Hainan Island between 2023 and 2024. A total of 2550 animals were collected, representing 14 Rodentia species, one Erinaceomorpha species, and one Scandentian species. Based on a statistical sampling framework, 1284 individuals were selected to generate 125 pooled gut samples for virome analysis. We identified 527 viral RNA species and recovered 175 complete or near-complete viral genomes. Remarkably, Rattus norvegicus and Rattus tanezumi accounted for 83.9% (442/527) of detected viral species, 68.6% (72/105) of novel viral sequences, and 88.6% (93/105) of cross-species viruses. Eight novel viruses showed recombination signals, seven originating from these two species. Among 13 human pathogenic viruses identified, 12 were detected in Rattus norvegicus and Rattus tanezumi. These findings suggest that these species may function as hub hosts for viral maintenance and spread, emphasizing the value of targeted surveillance to reduce future potential spillover risks.

Shrews represent an important reservoir of diverse human-pathogen viruses with implications for human infectious diseases. As the most populous shrew species, the Asian house shrew-Suncus murinus (Su. murinus) is widely distributed across South and Southeast Asia-particularly tropical and subtropical regions-yet its virome remains poorly studied. In this study, we collected 249 Su. murinus from 18 cities/counties (excluding Sansha) across Hainan Island and conducted RNA sequencing on gut, spleen, and lung tissues. We identified 192 RNA viruses, comprising 120 known viral species and 72 novel viruses, including key zoonotic viral families: Arenaviridae, Hantaviridae, Paramyxoviridae etc. We assembled 102 complete and nearly complete genomes. Notably, 64 known viruses exhibited cross-species transmission potential, including 57 with spillover risk and 7 human-pathogenic viruses: Mammarenavirus choriomeningitidis (LCMV), Henipavirus (HeV), Wenzhou virus (WENV), Langat virus (LGTV), Amur virus (AMRV), Influenza A virus (H1N1), and Rotavirus A (RVA). Additionally, AMRV, LGTV, and LCMV were reported here for the first time in Su. murinus based on metagenomic detection. Our phylogenetic and RT-PCR results indicate Su. murinus is a candidate reservoir for Langya-like henipavirus. Collectively, our study reveals tropical populations of Su. murinus are a previously underappreciated reservoir of viral diversity, underscoring their key role in zoonotic emergence and necessitating surveillance in tropical regions.

Three strains designated c1-l78T, c2-A9 and c3-l95 were isolated from blowhole swab samples of Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) in Hubei Province, China. The strains are Gram-stain-negative, oxidase-positive, catalase-positive, obligately aerobic, non-motile, non-haemolytic, proteolytic and short-rod-shaped bacteria. Based on 16S rRNA gene sequence analysis, strain c1-l78T was assigned to the family Moraxellaceae (order Pseudomonadales), with the genus Acinetobacter being its closest relative (93.96 % similarity). Average nucleotide identity and digital DNA-DNA hybridization values between c1-l78T and type strains of all validly published species of the genus Acinetobacter were very low, ranging from 71.2 to 73.2 % and 20.9 to 26.6 %, respectively. The average amino acid identity was 65.0-69.9 % with orthologous fraction (55.3-67.5 %), and the percentage of conserved proteins was 39.0-55.4 %. Phylogenomic analysis further confirmed a distinct lineage, supported by a high relative evolutionary divergence value of ~0.94. The DNA G+C content of strain c1-l78T is 39.1 mol %. The major cellular fatty acids were 9-octadecenoic acid (C18 : 1  ω9c), summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c) and hexadecanoic acid (C16 : 0). The sole respiratory quinone was ubiquinone-8, and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unknown aminophosphoglycolipid. Based on the polyphasic analysis, we propose that the three strains represent a novel genus and species, for which the name Hubeiibacter gen. nov., type species Hubeiibacter jixunmingi gen. nov., sp. nov. is proposed. The type strain is c1-l78T (=GDMCC 1.4970T=JCM 37696T).

Wildlife serves as a natural reservoir for emerging viruses. Although virome studies of bats and rodents have advanced our understanding of viral diversity, the virome characteristics and zoonotic risks of wildlife inhabiting the Qinghai-Tibet Plateau-a global biodiversity hotspot-remain poorly understood. Here, we conducted a virome survey of 22 wild animal species from the Qinghai-Tibet Plateau using meta-transcriptomic sequencing. We characterized the diversity and distribution of wildlife-associated viruses and found that birds tended to harbor higher viral diversity and abundance than mammals. In addition, greylag goose (Anser anser) and Himalayan vulture (Gyps himalayensis) harbored a high proportion of cross-species viruses and occupied central positions in the transmission network. In total, we identified 36 viral genera with pathogenic potential to humans or animals. Among them, several viruses, including rotavirus A (RVA) and parainfluenza virus 5 (PIV-5), pose a high risk of zoonotic transmission. Notably, the plateau vole (Neodon fuscus) carried the highest number of high-risk viruses, and the RVA strains it harbors represent a distinct early evolutionary lineage. These findings highlight the public health relevance of wildlife on the Qinghai-Tibet Plateau and emphasize the need for continued surveillance of high-risk hosts and viruses.

Four novel strains, designated p1-h21T/p2-l61 and p3-h83T/p4-l81, characterized as Gram-stain-negative, oxidase-positive, catalase-positive, obligately aerobic, non-motile and rod-shaped, isolated from blowhole swab samples of Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), collected from Hubei Province, China. Pairwise sequence comparisons of the 16S rRNA genes showed that these isolates were separated into two species. Strains p1-h21T and p2-l61 were most closely related to Paracoccus endophyticus SYSUP0003T (97.18% similarity) and Paracoccus aurantiacus TK008T (97.03% similarity), whereas strains p3-h83T and p4-l81 exhibited 96.89% similarity to Paracoccus kondratievae GBT, and 96.53% similarity to Phaeovulum vinaykumarii DSM 18714T. The DNA G+C contents of type strains p1-h21T and p3-h83T are 65.7 mol% and 66.9 mol%, respectively. These strains had summed feature 8 (comprising C18 : 1  ω6c and/or C18 : 1  ω7c) as major cellular fatty acids, ubiquinone 10 as the sole respiratory quinone and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine as major polar lipids, which are typical for members of the genus Paracoccus. However, the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the four novel strains and their reference strains (ANI <75.3%, dDDH <20.5%) are lower than the species delineation thresholds, along with distinct phenotypic and biochemical characteristics, distinguishing them from their closest relatives and other recognized Paracoccus species. Therefore, strains p1-h21T/p2-l61 and p3-h83T/p4-l81 represent two novel species in the genus Paracoccus, for which the names Paracoccus jiaweipingae sp. nov. and Paracoccus zhouxuedongae sp. nov. are proposed, with p1-h21T (=GDMCC 1.4971T=JCM 37697T) and p3-h83T (=GDMCC 1.4972T=JCM 37698T) as type strains.

Six novel bacterial strains, designated P01ᵀ, P02, P04ᵀ, P05, P06ᵀ and P07, were isolated from the intestinal contents of the Neodon fuscus collected from the Qinghai-Tibet Plateau, PR China. Cells were aerobic, non-motile, Gram-stain-positive, catalase-positive, oxidase-positive and rod-shaped. Strains P01ᵀ, P04ᵀ and P06ᵀ can grow at 4-37°C and tolerate 10.0% (w/v) NaCl. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene sequences and core genes indicated that the three strain pairs (P01T/P02, P04T/P05 and P06T/P07) were closely related to members of the genus Microbacterium, forming separate clades adjacent to Microbacterium hatanonis JCM 14558T, Microbacterium rhizomatis JCM 30598T and other Microbacterium strains. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between each strain (P01ᵀ, P04ᵀ and P06ᵀ) and the type strains of their closest relatives were all below the established species delineation thresholds (70% for dDDH and 95-96% for ANI). The major cellular fatty acids of all six strains were anteiso-C15:0 and anteiso-C17:0. All novel type strains shared diphosphatidylglycerol, phosphatidylglycerol and one or two unidentified GLs as their predominant polar lipids. The peptidoglycan amino acids consisted of alanine, glutamic acid, glycine and ornithine. Menaquinones identified in these strains were MK-9, MK-11 and MK-13. In terms of cell-wall sugars, as determined by TLC, rhamnose, ribose, glucose and galactose were common to all three strains; additionally, mannose was detected in P04ᵀ, and both mannose and xylose were present in P06ᵀ. All these analyses concluded that these six strains represent three novel members of the genus Microbacterium, for which the names Microbacterium songi sp. nov., Microbacterium hanjuni sp. nov. and Microbacterium shimangi sp. nov. are proposed. The type strains are P01ᵀ (GDMCC 1.4682 T=JCM 37688T), P04ᵀ (=GDMCC 1.4683T=JCM 37689T) and P06ᵀ (=GDMCC 1.4684T=JCM 37690T), respectively.

What is already known about this topic?:Lymphocytic choriomeningitis virus (LCMV) is transmitted primarily through rodent excreta, with humans being universally susceptible to infection. Transmission via organ transplantation occurs rarely. The predominantly nonspecific clinical presentation in humans has contributed to LCMV remaining an underrecognized zoonotic pathogen. What is added by this report?:This study provides the first serological confirmation of past LCMV infection among the general population in Gansu Province, with seroprevalence rates of 18.31% by enzyme-linked immunosorbent assay (ELISA) and 1.97% by immunofluorescence analysis (IFA). Priority populations for targeted LCMV prevention and control interventions include rural residents, individuals with lower educational attainment, and agricultural workers. What are the implications for public health practice?:LCMV clinical manifestations overlap with those of pathogens targeted by national sentinel surveillance systems; LCMV should be incorporated into future screening protocols for unidentified infectious agents.

Probiotics can reduce the incidence of respiratory syncytial virus (RSV) disease in premature infants; this approach is resource‐intensive and less expensive than other strategies and easier to implement than most current methods worldwide. Traditional lactic acid‐producing bacteria are the main probiotics that have been studied for RSV treatment. Marine probiotics promote the survival, immunity, and disease resistance of aquatic plants and animals. However, relatively little research has been conducted on viral infections in humans. Here, we report a slightly halophilic and extremely halotolerant marine bacterium, Paraliobacillus zengyii , which has antiviral activity and grows at a relatively low temperature (28°C). We found that P. zengyii inhibited RSV infection by regulating the interferon (IFN) response both in vitro and in vivo. P. zengyii significantly increased the RSV‐induced phosphorylation of TBK1 and IRF3 and the expression of antiviral factors interferon‐induced transmembrane protein 1 (IFITM1) and interferon‐induced transmembrane protein 3 (IFITM3). Furthermore, P. zengyii upregulated Sendai virus (SeV)‐ and poly(I:C)‐induced IFN‐β expression. These results indicate that the marine bacterium P. zengyii inhibits RSV infection and increases IFN‐β production in response to RSV, SeV infection, or poly(I:C) stimulation. Consequently, P. zengyii has potential as a broad‐spectrum anti‐RNA virus probiotic.

Paraliobacillus zengyii CGMCC1.16464 (P. zengyii) is a novel antiviral probiotic candidate strain. To ensure its safety as a potential probiotic, a safety evaluation was conducted in this study. The safety and functional potential of P. zengyii were systematically assessed through genomic bioinformatics analysis, in vitro experiments, and acute oral toxicity tests in mice. Genomic analysis revealed that P. zengyii is rich in genes related to carbohydrate and amino acid metabolisms and carries genes encoding antimicrobial and antiviral agents (such as ectoine, type III polyketide synthase, and lasso peptides). It also expresses gastrointestinal tolerance-related proteins (ClpC, GroEL, and ClpP). Its resistance to polymyxins is an inherent trait with no risk of plasmid-mediated transfer. In vitro experiments confirmed that P. zengyii is somewhat tolerant to bile salts and acidic environments and does not exhibit hemolytic or gelatinase activity. Importantly, an acute oral toxicity test in mice revealed that after intervention with high, medium, or low doses, no significant abnormalities in the body weight, organ index, or tissue morphology of the mice were observed. In conclusion, P. zengyii exhibited good safety and probiotic potential in terms of genomic safety, metabolic function, and in vitro and in vivo toxicities, providing a theoretical basis for the development of novel functional probiotics.

Six aerobic, Gram-stain-positive, non-motile, rod-shaped bacterial strains (P13 T , P18, P16 T , P17, P20 T and P15) were isolated from the intestinal contents of the plateau vole ( Neodon fuscus ) collected from the Qinghai–Tibet Plateau, PR China. Phylogenetic analyses showed that these isolates formed three well-separated lineages in all phylogenetic and phylogenomic trees comprising members of the genus Herbiconiux . The average nucleotide identity and digital DNA–DNA hybridization values between the three novel type strains (P13 T /P16 T /P20 T ) and other known species in this genus were all below the thresholds of 95–96% and 70%. Analysis of fatty acid profiles showed anteiso -C 15:0 and anteiso -C 17:0 as the major fatty acids for all six strains. All novel type strains had diphosphatidylglycerol, phosphatidylglycerol and unidentified glycolipids 2 as the major polar lipids. The peptidoglycan amino acids of these three type strains consisted of alanine, glutamic acid, glycine and 2,4-diaminobutyric acid. All novel type strains had MK-11 and MK-10 as the predominant respiratory quinone. The DNA G+C contents of strains P13 T , P16 T and P20 T were 70.0, 69.0 and 70.0 mol%, respectively. Based on genotypic, phenotypic, phylogenetic and biochemical properties, the six novel strains represent three novel species in the genus Herbiconiux , for which the names Herbiconiux liangxiaofengii sp. nov. (type strain P13 T =GDMCC 1.4677 T =JCM 37540 T ), Herbiconiux wuyangfengii sp. nov. (type strain P16 T =GDMCC 1.4678 T =JCM 37541 T ) and Herbiconiux liukaitaii sp. nov. (type strain P20 T =GDMCC 1.4681 T =JCM 37542 T ) are proposed, respectively.

The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) is a critically endangered freshwater cetacean that is endemic to China. In this study, we conducted viromic analysis on swab and tissue samples from three stranded individuals collected in 2024, using high-throughput meta-transcriptomic sequencing. A diverse range of viral sequences was identified, including a large proportion of unclassified viruses, bacteriophage-related viruses, and vertebrate-associated viruses. Notably, we assembled the complete genome sequence of a novel papillomavirus, designated Neophocaena asiaeorientalis papillomavirus isolate WH240216 (NasiPV-WH240216), which shares 82.2% overall nucleotide sequence identity and 87.5% L1 gene identity with Phocoena spinipinnis papillomavirus 1 (PsPV1). The genome is 8,010 bp in length and exhibits the typical genome organization and conserved protein motifs of a papillomavirus. Phylogenetic analysis placed this virus within the genus Omikronpapillomavirus, and its sequence divergence met the ICTV criteria for a novel papillomavirus type. These findings expand our knowledge of the diversity of papillomaviruses in cetaceans and provide important insights into the evolution and potential pathogenicity of marine mammal papillomaviruses.

Enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease (HFMD), leading to a serious health threat to young children. Probiotics are effective at treating or preventing gastrointestinal infections, especially viral infections. Probiotics against EV71 are mainly traditional lactic acid-producing bacteria, and most of them have been proven to be effective only in vitro. Here, we report that the marine bacterium Paraliobacillus zengyii X-1125 (P. zengyii) has promising anti-EV71 activity. The antiviral effect of P. zengyii against EV71 was assessed in different cell lines, and the viral RNA levels and titers were obviously reduced after treatment with P. zengyii. Furthermore, we established an EV71-infected mouse model to evaluate its antiviral efficacy in vivo. The oral administration of P. zengyii significantly decreased the viral loads in the hindlimb muscles, spleens, and ileums. Further research revealed that P. zengyii enhances the expression of type I interferon (IFN-I) in EV71-infected cells. Similarly, transcriptome analysis indicated that the expression of interferon-stimulated genes (ISGs) in EV71-infected mice significantly increased after P. zengyii treatment. Taken together, the results of this study indicated that P. zengyii markedly reduces EV71 infection by regulating the IFN response both in vivo and in vitro, providing a potential means to work against EV71 infection.

BackgroundHand, foot, and mouth disease (HFMD) has remained a serious public health threat since its first outbreak in China. Analyzing the province-level spatiotemporal distribution of HFMD and mapping the relative risk in mainland China will help determine high-risk provinces and periods of infection outbreaks for use in formulating new priority areas for prevention and control of this disease. Furthermore, our study examined the effect of air pollution on HFMD nationwide, which few studies have done thus far.MethodsData were collected on the number of provincial monthly HFMD infections, air pollution, meteorological variables, and socioeconomic variables from 2014 to 2017 in mainland China. We used spatial autocorrelation to determine the aggregate distribution of HFMD incidence. Spatiotemporal patterns of HFMD were analyzed, risk maps were developed using the Bayesian spatiotemporal model, and the impact of potential influencing factors on HFMD was assessed.ResultsIn our study, from 2014 to 2017, the HFMD annual incidence rate in all provinces of mainland China ranged from 138.80 to 203.15 per 100,000 people, with an average annual incidence rate of 165.86. The temporal risk of HFMD for 31 Chinese provinces exhibited cyclical and seasonal characteristics. The southern and eastern provinces had the highest spatial relative risk (RR > 3) from 2014 to 2017. The HFMD incidence risk in provinces (Hunan, Hubei, and Chongqing) located in central China increased over time. Among the meteorological variables, except for the mean two-minute wind speed (RR 0.6878; 95% CI 0.5841, 0.8042), all other variables were risk factors for HFMD. High GDP per capita (RR 0.9922; 95% CI 0.9841, 0.9999) was a protective factor against HFMD. The higher the birth rate was (RR 1.0657; 95% CI 1.0185, 1.1150), the higher the risk of HFMD. Health workers per 1,000 people (RR 1.2010; 95% CI 1.0443, 1.3771) was positively correlated with HFMD.ConclusionsFrom 2014 to 2017, the central provinces (Hunan, Hubei, and Chongqing) gradually became high-risk regions for HFMD. The spatiotemporal pattern of HFMD risk may be partially attributed to meteorological and socioeconomic factors. The prevalence of HFMD in the central provinces requires attention, as prevention control efforts should be strengthened there.

Emerging zoonoses of wildlife origin caused by previously unknown agents are one of the most important challenges for human health. The Qinghai-Tibet Plateau represents a unique ecological niche with diverse wildlife that harbours several human pathogens and numerous previously uncharacterized pathogens. In this study, we identified and characterized a novel arenavirus (namely, plateau pika virus, PPV) from plateau pikas (Ochotona curzoniae) on the Qinghai-Tibet Plateau by virome analysis. Isolated PPV strains could replicate in several mammalian cells. We further investigated PPV pathogenesis using animal models. PPV administered via an intraventricular route caused trembling and sudden death in IFN alpha beta R-/- mice, and pathological inflammatory lesions in brain tissue were observed. According to a retrospective serological survey in the geographical region where PPV was isolated, PPV-specific IgG antibodies were detected in 8 (2.4%) of 335 outpatients with available sera. Phylogenetic analyses revealed that this virus was clearly separated from previously reported New and Old World mammarenaviruses. Under the co-speciation framework, the estimated divergence time of PPV was 77-88 million years ago (MYA), earlier than that of OW and NW mammarenaviruses (26-34 MYA).

The great majority of microbial species remain uncultured, severely limiting their taxonomic characterization and biological understanding. The plateau pika ( Ochotona curzoniae ) is a small burrowing steppe lagomorph that is endemic to the Qinghai-Tibetan Plateau and is considered to be the keystone species in the maintenance of ecological stability.

Lassa virus (LASV) is a significant human pathogen causing hemorrhagic fever in West Africa. Increased traveling around the world raises the risk of imported cases to other countries. Lassa virus (LASV) is a causative agent of hemorrhagic fever epidemic in West Africa. In recent years, it has been transmitted several times to North America, Europe, and Asia. Standard reverse transcription (RT)-PCR and real-time RT-PCR are extensively used for early detection of LASV. However, the high nucleotide diversity of LASV strains complicates the development of appropriate diagnostic assays. Here, we analyzed LASV diversity clustered with geographic location and evaluated the specificity and sensitivity of two standard RT-PCR methods (GPC RT-PCR/1994 and 2007) and four commercial real-time RT-PCR kits (namely, Da an, Mabsky, Bioperfectus, and ZJ) to detect six representative LASV lineages using in vitro synthesized RNA templates. The results showed that the GPC RT-PCR/2007 assay had better sensitivity compared to the GPC RT-PCR/1994 assay. The Mabsky and ZJ kits were able to detect all RNA templates of six LASV lineages. Contrastingly, the Bioperfectus and Da an kits failed to detect lineages IV and V/VI. The limit of detection for lineage I with the Da an, Bioperfectus, and ZJ kits were significantly higher than that of the Mabsky kit at an RNA concentration of 1 x 10(10) to 1 x 10(11) copies/mL. The Bioperfectus and Da an kits detected lineages II and III at an RNA concentration of 1 x 10(9) copies/mL, higher than that of the other kits. In conclusion, the GPC RT-PCR/2007 assay and the Mabsky kit were suitable assays for the detection of LASV strains based on good analytical sensitivity and specificity.IMPORTANCE Lassa virus (LASV) is a significant human pathogen causing hemorrhagic fever in West Africa. Increased traveling around the world raises the risk of imported cases to other countries. The high nucleotide diversity of LASV strains clustered with geographic location complicates the development of appropriate diagnostic assays. In this study, we showed that the GPC reverse transcription (RT)-PCR/2007 assay and the Mabsky kit are suitable for detecting most LASV strains. Future assays for molecular detection of LASV should be based on specific countries/regions along with new variants.

目的 对2022年湖北省人和家养动物血清中荆门蜱病毒(JMTV)的抗体阳性率进行初步研究,评估荆门蜱病毒感染人群和动物的风险.方法 将JMTV NS3蛋白在大肠埃希菌中表达并纯化,制备ELISA包被抗原,利用人和动物血清分别确定cut-off值;收集湖北省多个市牛羊养殖场采集的牛、羊血清,武汉市中心医院体检健康人血清,对这些血清样本以及实验室保存的林区居民血清进行JMTV特异性抗体以及核酸检测.结果 初步建立基于NS3蛋白的JMTV抗体检测酶联免疫吸附试验(ELISA).确定人血清、牛血清和羊血清的cut-off值分别为0.342、0.098和0.298.44份牛血清和193份羊血清中JMTV抗体阳性率分别为4.55％和3.63％.174份体检健康人和13份林区居民血清JMTV抗体结果均为阴性.所有样本中均未检测到JMTV的核酸片段.结论 家养动物牛、羊血清中检出JMTV特异性抗体,提示需关注牛、羊作为蜱携带者导致病毒扩散的风险.

Maopu buckwheat finished Baijiu (MBFB), a unique Chinese Baijiu, is mainly composed of base Baijiu and tartary buckwheat extract (TBE). However, there is a lack of studies reporting its flavor. In this study, the key odorants in MBFB were characterized for the first time using a sensomics approach. Forty-nine odorants were identified using gas chromatography-mass spectrometry/olfactory analysis, coupled with aroma extraction dilution analysis. They were quantified using multiple methods and their odor activity values were calculated. Ethyl hexanoate, ethyl butanoate, butanoic acid, hexanoic acid, dimethyl trisulfide, p-cresol, β-damascenone, and 3-methylbutanal were confirmed as the key odorants in MBFB using recombination and omission experiments. Furthermore, the interaction between TBE and odorants were revealed that TBE enhanced the sweet notes, while it inhibited the alcoholic, acidic, and fruity notes, which might be because TBE promoted the volatility of most esters, but inhibited the volatilities of butanoic acid and hexanoic acid.

[目的]分离喜马拉雅旱獭肠内容物样本中的噬菌体,并研究其生物学特性和基因组特征.[方法]以大肠杆菌为宿主菌,利用双层琼脂平板法从喜马拉雅旱獭肠内容物样本中分离噬菌体;用透射电镜观察形态特征;测定其最佳感染复数、一步生长曲线、酸碱耐受度及宿主裂解谱等生物学特性,并进行全基因组测序.[结果]从喜马拉雅旱獭肠内容物样本中分离得到一株裂解性大肠杆菌噬菌体,命名为vB EcoM_TH18,其噬菌斑呈无晕环的透亮圆形,透射电镜观察发现该噬菌体头部直径为(90±5)nm,尾部长度为(115±5)nm;最佳感染复数为1;一步生长曲线显示其潜伏期为10 min,110 min后进入平台期,平均裂解量为15 PFU/mL;在pH4.5-9.5的范围内具有稳定活性;可裂解多种致病型和血清型大肠杆菌和宋内志贺氏菌,无法裂解沙门氏菌、屎肠球菌、金黄色葡萄球菌、肺炎克雷伯杆菌及鲍曼不动杆菌;基因组测序结果表明,其基因组长度为133 882 bp,GC含量为39.95％.基因组共注释到210个编码序列(CDS)和13个tRNAs,不含毒力基因及耐药基因.BLASTn比对结果表明该基因组与Avunavirus属噬菌体Av-05同源性为95.17％.基于噬菌体全基因组、主要衣壳蛋白和终止酶大亚基分别构建系统进化树,结果表明vB_EcoM_TH18是一株肌尾噬菌体科(Myoviridae)Avunavirus属的新型噬菌体.[结论]从喜马拉雅旱獭肠内容物中成功分离并鉴定了一株新型宽谱大肠杆菌噬菌体vB_EcoM_TH18,可裂解多种致病型和血清型的大肠杆菌及宋内志贺菌.

The United Nations Secretary-General Mechanism (UNSGM) for investigation of the alleged use of chemical and biological weapons is the only established international mechanism of this type under the UN. The UNGSM may launch an international investigation, relying on a roster of expert consultants, qualified experts, and analytical laboratories nominated by the member states. Under the framework of the UNSGM, we organized an external quality assurance exercise for nominated laboratories, named the Disease X Test, to improve the ability to discover and identify new pathogens that may cause possible epidemics and to determine their animal origin. The “what-if” scenario was to identify the etiological agent responsible for an outbreak that has tested negative for many known pathogens, including viruses and bacteria. Three microbes were added to the samples, Dabie bandavirus, Mammarenavirus, and Gemella spp., of which the last two have not been taxonomically named or published. The animal samples were from Rattus norvegicus, Marmota himalayana, New Zealand white rabbit, and the tick Haemaphysalis longicornis. Of the 11 international laboratories that participated in this activity, six accurately identified pathogen X as a new Mammarenavirus, and five correctly identified the animal origin as R. norvegicus. These results showed that many laboratories under the UNSGM have the capacity and ability to identify a new virus during a possible international investigation of a suspected biological event. The technical details are discussed in this report.